Seaweed house nominated for international design award

Traditional Læsø building techniques on show in sustainable summer house

In 2012, the property portfolio company Realdania Byg held a competition to reinterpret a local building tradition on the island of Læsø, northeast of the Jutland Peninsula. The architectural firm Vandkunsten won the competition, and now its entry, ‘the modern seaweed house’ (‘Det Moderne Tanghus’), has been nominated for the international design prize 'Index Design to Improve Life'.

Traditional technique
Jørgen Søndermark, the project leader at Realdania Byg, explained to the engineering publication Ingeniøren that the house develops the technique of using seaweed as insulation.

“For generations the residents of Læsø have used seaweed as roofing material,” he said.

“In this modern interpretation we have gone a step further and used seaweed in three different ways: as insulation, interior-padded cladding and visible protective cladding on the outer walls and the roof.”

As well as being traditional, Søndermark emphasises that seagrass is a sustainable resource. “We carried out the project partly to demonstrate the possibilities of going back to a time when sustainability was compulsory, and specifically to show what seagrass can do in a modern sustainable context,” he said.

The house lives up to 2020 CO2 standards and is designed to offset the CO2 footprint of its construction within 20 years.

The winner of the 2015 Index Design to Improve Life prize will be announced in August.




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